I went back and read your original post... You mentioned trying to find a ground for a gauge and kept mentioning the "passenger side fuse box"... I'm assuming you are talking about the one in the engine compartment. You also talked about the Tyco plug on the fuse box coming loose.... Again I assume we are still talking about inside the engine compartment.
So my question is when did we get inside the car to the SJB? I'm not real clear as to why the SJB is suspect.
If you were messing with the connections at the fuse box in the engine compartment and the connector came loose... I would be starting there. You might have to probe each wire just away from the plug and see if each wire that is supposed to be connected to a fuse is actually making contact with the wire.
I originally suspected the sjb(in my words the pass side fusebox in the kick panel) due to my opening up the panel and the front connector coming off while the battery and car was still powered. There are two connectors on the front, the one that came loose was the wide one with the latch right above the fuse panel door, not the skinny one on the top left. So the Tyco latched switch that came off was from the sjb front.
I never attempted to get anything from the bec. I only went to the bec after the sjb looking for a problem. I only suspected the sjb die to other members opinions on here and a little online research. I do not have any burnt fuses on the sjb or bec. I have checked many times, I have also tested all the relays and clear top fuses/ those two black top fuses or circuits with the 1 on them in bec.
I opened up the bec and I could not see any signs of burns or anything going bad. I was still under the impression that something internally got pushed out when I pushed in the add a fuse, my faulty attempted ground fried something, or I ruined my sjb when that connector up front came off.
I attempted to ground my gauge to the bolt on the bottom right of the sjb and I tried tapping into the open fuse slot with a littlefuse add a fuse/circuit with a 5a minifuse.
I made the attempt to later put the key to acc, never turned on and I had that bad feeling in my chest that something went wrong. I never had any electrical issues before I botched this install. So this problem came that night from my mishap.
The night after the install I had power to everything and the only obvious problem was a heartbeat or ticking sound coming from my cluster. Then the next day cones and I have limited power to certain items, I try to diagnose the problem and two days later literally nothing works.
Thanks for the time guys, sorry for the lengthy reply above.